Conservation of ancient copper coinage

I have no experiences with marine coinage--I am working mainly on
archaeological coins. But you don't mention for me most important
part of cleaning of archaeological cooper alloys--especially for
heavily corroded objects with just traces of metal core or without
metal core--mechanical cleaning.

I am mainly using--and could heartily recommend for cleaning of
archaeological copper alloys--mechanical cleaning (scalpels,
brushes, gentle blasting with glass bead or wall nut shells). I know
it is much more time consuming and expensive but you could be really
control what you would like to remove and what not. Other advantage
of mechanical cleaning is that you have no chemical residues in
porous corrosion layers. Details of the legend or type are normally
preserved only in corrosion layers so for me as I already wrote is
much more suitable to use mechanical cleaning instead of chemical
cleaning.

Dusan Perlik
NTNU Museum of Natural History and Archaeology
NO-7491 Trondheim
Norway


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                  Conservation DistList Instance 22:54
                 Distributed: Wednesday, March 25, 2009
                       Message Id: cdl-22-54-010
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